Arkush: Final dress rehearsal for Bears

The Bears will roll into Oakland for their third game of the preseason and final dress rehearsal for the regular season with starters with a full agenda and a long wish list as well.

First up for Marc Trestman’s team is to get the offense rolling both through the air and on the ground. They need to pile up some yardage and points and try to accomplish that task with multiple weapons while securing the right side of the offensive line.

On its face, this game and this opponent appear to offer the offense a perfect canvas on which to paint. The Raiders were one of the worst defenses in the NFL in 2012 and a number of its best players like Richard Seymour, Tommy Kelly, Michael Huff and Philip Wheeler are gone.

True, a few solid veteran journeymen including Kevin Burnett, Tracy Porter, former Bear Nick Roach and future Hall of Famer Charles Woodson have been added. But this is a defense the Bears should beat, and beat up on if they are truly improved on offense.

Most importantly, Kyle Long and Jordan Mills need to put firm grips on their starting spots at right guard and right tackle as Trestman has now said Jermon Bushrod, Matt Slauson and Roberto Garcia are definitely the other three starters.

The Raiders were 18th vs. the run last year and 30th rushing the passer and the only defensive lineman on the roster of note is 13-year veteran Andre Carter, who will be a backup at end and situational pass rusher. Long and Mills must win the night to allow Trestman and Jay Cutler any confidence heading into the season.

The hysteria over Cutler focusing on Brandon Marshall against the Chargers was over - the - top silly, but with a full half and possibly a series in the third quarter it is critical that Cutler shows he knows where all his weapons are, and perhaps more critical that Martellus Bennett, Alshon Jeffery and at least one wide receiver among Joe Anderson, Marquess Wilson and Devin Aromashodu prove they’re worthy of his attention.

Earl Bennett will almost certainly be a spectator. But Steve Maneri, Fendi Onobun, Leonard Pope, Kyle Adams and Gabe Miler cannot afford to again be the spectators they’ve been on the field in the first two preseason games. I believe the Bears would especially like to see Onobun take the No. 2 tight end job.

Defensively, while the Bears certainly aren’t worried about him, it will be really nice to see Julius Peppers take his first snaps of the season, and Mel Tucker wants to see consistent and ferocious pressure on Raiders QB Matt Flynn every time he goes into his nickel package with Peppers, Corey Wootton and Shea McClellin all rushing the passer at the same time.

It is also critically important that the Bears find a fourth defensive tackle. Henry Melton and Stephen Paea are locked into the starting lineup and Nate Collins appears to be a very solid No. 3. But the Bears will play a three-man rotation at tackle and with Melton out with a concussion or should any of the three get nicked during the season, depth is critical. At the moment, there doesn’t appear top be any.

Most importantly for the defense, Jon Bostic needs to take a big step forward in Oakland. He’s had a nice training camp for a rookie and shows great promise, but that does you no good in Week 1 when he is your starter, which he is clearly going to be. D. J. Williams will not be ready.

What’s interesting here is when they run Darren McFadden, Marcel Reece and Rashad Jennings at you. This is the one area where the Raiders can be a lot more than the JV when they’re healthy. This is going to be the hardest and biggest final exam of Bostic’s young life and Bears fans have to hope he gets to the right place at the right time a lot more than he has so far.

• Hub Arkush covers the Bears for Shaw Media and HubArkush.com. Write to him at harkush@shawmedia.com.